The Creator’s Guide to Post Sizes: Understanding Dimensions for Instagram, Flyers & Mobile Media (Without the Headache)

If you’ve ever tried to upload a photo to Instagram and it mysteriously cropped off your forehead… or your flyer suddenly looks blurry even though it looked perfect on your phone… this post is for you. Let’s break down post dimensions in a way that’s actually useful, easy to remember, and perfect for anyone managing their brand, promoting events, or just trying to look aesthetically correct online. Whether you're a client of IAC Media, a small business owner, a creator, or a “my friend asked me to post this flyer” type of person — this is your cheat sheet.

01. Why Dimensions Matter

Every platform crops or displays content differently. When you use the wrong size, you get:

• Blurry graphics (stretching + compression)

• Cut-off text (your “Happy Birthday Briaa—” stops mid-name)

• Weird framing (your face is there, but also somehow… not)

• Unprofessional presentation (brands lose trust fast)

Correct dimensions mean:

✨ Crisp✨ Clean✨ Correctly displayed✨ And your content sits on the feed exactly how you intended

Let’s break it all the way down.

02. Instagram Sizes You Need to Know (The Bible for Creators)

Instagram has three main formats: Posts, Stories, Reels.Here’s the simplest breakdown:

A. Square Instagram Post (The Default)

Size: 1080 × 1080 px Ratio: 1:1

Use this for:

• Quotes

• Product shots

• Sale announcements

• Brand graphics

Why: Classic, centered, never cropped weirdly.

B. Portrait Instagram Post (Tall & Attention-Grabbing)

Size: 1080 × 1350 px Ratio: 4:5

Use this for:

• Aesthetic lifestyle photos

• Flyers with a lot of information

• Anything you want to appear larger on the feed

Why: Takes up the most feed real estate. Best for engagement.

C. Landscape Post (Wide Photo / Clips)

Size: 1080 × 566 px Ratio: 1.91:1

Use this for:

• Cinematic photos

• Wide shots

• Videos exported in horizontal format

Note: Least used now, but still relevant.

03. Instagram Stories & Reels (The Full-Screen Queens)

A. Instagram Story

Size: 1080 × 1920 px Ratio: 9:16

Use this for:

• Announcements

• Flyers

• Behind-the-scenes

• Polls & engagement slides

• Links / testimonials / client highlights

Important:Stories are FULL SCREEN. Do not upload square images expecting them to fill the space. That's how you get crop chaos.

B. Instagram Reel

Size: 1080 × 1920 px Ratio: 9:16

Use this for:

• Vertical video content

• Tutorials

• Recaps

• Voiceovers

Tip :Avoid placing text too high or low — Instagram’s UI can cover it (username at top, caption at bottom).

04. When You’re Using the WRONG Size (and How to Know)

You are likely using the wrong size when:

• Your image uploads blurry → resolution is too low

• Instagram crops text → wrong ratio

• A flyer looks zoomed in → designed square but posted vertically

• Black bars show up on the sides → not formatted full screen

• Your video looks grainy → exported at low resolution or wrong aspect ratio

The fix:

✔ Always design or export in 1080 px width minimum✔ Use platform-specific ratios✔ In Canva — choose the correct template from the start✔ If resizing, check that nothing moves, shifts, or gets cropped

05. The “What Size Do I Use?” Cheat Sheet

Use this table for instant reference:

Format	Size	Ratio	Best For
Square Post	1080×1080	1:1	Quotes, promos, product shots
Portrait Post	1080×1350	4:5	Flyers, lifestyle, brand graphics
Landscape	1080×566	1.91:1	Cinematic shots, wide photos
Story	1080×1920	9:16	Announcements, ads, polls, links
Reel	1080×1920	9:16	Vertical video content

06. How to Choose the Right Size for Flyers

For clients specifically (like Ebun asking “what is post size?”):

If the flyer is meant for the Instagram Feed

➡️ 1080 × 1350 px

If it’s meant for Stories & Full Screen

➡️ 1080 × 1920 px

If you want the same flyer in multiple formats

➡️ Duplicate → Resize → Adjust text for each layout

No cropping. No quality loss. No confusion.

07. What's Coming Soon to IAC Media (Optional Section for Your Blog)

At IAC Media, all client deliverables come in:

• Feed size (1080×1350)

• Story size (1080×1920)

• Thumbnail versions when needed

• High-res printable versions (for physical flyers/posters)

Meaning: you’ll always have everything you need to post confidently on any platform.

08. Final Note: Your Graphics Speak Before You Do

Good design isn’t just about aesthetic — it’s about clarity, readability, and making sure your brand lands the way you intend.

When your dimensions are correct:

• Your message hits

• Your brand looks intentional

• Engagement improves

• You save time, money, and stress

If you ever need graphics resized, optimized, or fully branded — IACMedia.co is here for you.